BOTTARI, A, and B. FEDERICO. “P- Waves Reflected from the "20‘ Discontinuity’ Beneath the Mediterranean Region”. Annals of Geophysics 28, no. 1 (November 25, 1975): 77–96. Accessed June 24, 2026. https://www.annalsofgeophysics.eu/index.php/annals/article/view/4892.